Alloy compositions



g specified amounts of cobalt.

Patented Feb. 14, 1939 UNITED- STATES PATENT orr ca ALLOY oomosmons Joseph v. Emmons, Shlkel' 11mm, 01110. aimor to The Cleveland Twist Drill Cleveland, Ohio, a corporation of Ohio No Drawing. Original application 1934, Serial No. 741.532.

August 27 Divldedand this plication August 18, 1938, Serial N0. 225,578

The presentinvention is, in effect, an extensionof the teaching in this prior patent, particularly with respect to variations in the carbon, manganese, silicon, and chromium percentages, as well as the inclusion in such class of compositions of It is among the objects of my invention to provide alloy compositions of the same general character as those disclosed in my above identified prior patent, but which, due to variations in .theamounts of certain of the alloying elements used, are better suited for certain purposes than the compositions: defined in such prior patent.

Other objects of 'my invention will appear'as the description proceeds.

To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims.

The following description sets forth in detail some approved combinations of ingredients embodying my invention, suchdisclosed means constituting, however, but a few of the various forms in which theprinciple of the invention may be used.

My invention may be, as above indicated, stated in general terms as comprising the discovery that certain variations in the composition or compositions disclosed in my aforementioned prior patent result in alloys, particularly useful for certain purposes; more specifically, the present invention relates to variations in the amounts of carbon, manganese, silicon, and chromium and to the use of specified amounts of cobalt.

In accordance with my present invention, an

Cobalt 1.00 to 16.00

the remainder being substantially iron together with such other alloying ingredients andi'mpuritiesas are sometimes found in this type of alloy compositions.

A somewhat narrower range of percentages within which the various alloying ingredients may be present in this, type of steel is as follows:-

Per cent Carbon 0.60 to 0.90 Manganese 0.04 to 1.00 Silicon 0.10 to 0.45 Chromi 2.50 to 10.00 Tungsten 1.00 to 2.50 Vanadium 0.25 to 2.50 Molybdenum 6.00 to 12.00 Cobalt 2.00 to 10.00

the remainder being substantially iron, together with such other alloying ingredients and impurities as are sometimes found in alloying compositions of this type.

Several varieties or specific examples of the cobalt" type of alloy compositions falling within the above given ranges of percentages for the various ingredients, arranged in the order of their cobalt content, are as follows:

Donated below the remainder being substantially iron together with such other alloying elements and impurities as are sometimes found in this type of alloy compositions.

Attention is particularly directed to the fact that alloy compositions numbered 1, 5, 6, 7, 13 and 15 in the foregoing table of cobalt-including alloy compositions are also characterized by their high silicon content.

Compositions numbered 1 and 12 are particularly characterized by being vanadiumfree" and composition numbered 13 is characterized by being chromium-free as hereinafter defined.

- Attention is directed to compositions numbered 9,110, 11', 14 and 15, which are characterized by being mrec".

Example 0 Mn Si 01' W V Mo 00 Per- Pcr- Per- Per- Per- Pcr- Percent cent cent cent cent cent cent 0.40 2. 76 3.50 I. 50 None 8. 00 l. 00 .08 34 2. 57 1. 98 l. 01 7. l3 2. 15 .08 .23 2.83 1.94 1.07 6.79 3.97 08 37 3. 58 2. l2 2. l0 6. 29 3. 98 .30 1.00 10.00 1.00 0.25 4.00 4.00 .30 1.25 3.25 1.75 1.00 9.25 4.00 .30 2.25 5.25 1.75 1.00 7.00 4.00 .07 .37 3.53 1.84 1.00 6.60 4.05 .04 .27 3.78 1.77 1.08 0.90 4.07 .04 .36 3.78 1.04 1.11 7.54 4.13 .03 .49 3.65 1.77 1.08 6.86 5.91 .60 .30 1.60 1.50 None 8.00 7.50 30 l. 25 None 2. 00 l. 50 9. 00 8. 50

None 24 3. 50 l. 97 94 ll. 07 9. 34

None 90 3. 00 1.150 1. 00 8.00 13. 00

tures at which full hardness and strength may be developed.

The cobalt addition also increases somewhat the maximum attainable hardness and appears to slightly increase the resistance of the steel to tempering. Cutting tools such as drills made from many of the above examples have shown a high order 0! cutting quality, which in some cases has been observed to be greater than that of similar steels containing no cobalt.

The above example numbered 14 has shown excellent physical properties and a high degree of cutting quality when made into drills. This cutting quality was, in fact, better than that of drills made of 18-4-1 high speed steel with which comparisons were made.

The importance of chromium-free alloy compositions is also great as chromium is only obtainable in small quantities in this country. It is believed that alloy compositions such as Example 13, above given, will have a useful field as tool materials, especially so should chromium be dimcultly obtainable.

As previously indicated, compositions of the general class disclosed herein are similar to the general class disclosed in my prior Patent No. 1,937,334" with respect to the tungsten and molybdenum content, i. e., the amount of tungsten in the compositions may be broadly stated as comprising about 5% to about 40% of the amount of molybdenum present. A somewhat narrower range of proportional relationships between tungsten and molybdenum contemplates the use of tungsten in amounts from 10% to 30% of the amount of molybdenum present. The broad range of from 5% to 40%, above referred to, may be conveniently divided into the following groups, viz.-:5% to 16%, 16% to 25% and 25% to 40%.

Attention is directed to the fact that certain of the examples included in the foregoing description of my invention may be readily nitrided.

As is well known to those familiar with the art, any specification for a particular alloy composition must permit of certain variations due to the fact that in making up the composition, it is extremely diflicult, if not impossible, to commercially produce a composition exactly like a given specification. v

It is to be understood, therefore, that throughout the description and claims where I have used figures to denote deflnlteamounts and ranges, such amounts and ranges are to be construed-to include the range of variations usually permissible in making up alloy compositions to given specifications.

It should be noted that where the term none" is used to denote the absence of silicon, manganese, chromium and vanadium, or where an alloy composition is indicated as being free from any one or more of these elements, the construction to be placed upon these terms is a commercial absence of the elements in question. Silicon, manganese, chromium and vanadium may be considered as commercially absent if they are present in amounts less than 0.05%.

Other modes of applying the principle of my invention may be employed instead of the one explained, change being made as regards the materiais employed, provided the ingredients stated by any of the following claims or the equivalent of such stated ingredients be employed.

I, therefore, particularly point out and distinctly claim as my invention:

1. A ferrous alloy composition comprising:

Per cent Carbon About 0.30 to about 1.60 Molybdenum About 0.60 to about 15.00 Tungsten About 0.20 to about 6.00 Cobalt About 1.00 to about 16.00 Silicon About 0.05 to about 3.00 Manganese About 0.04 to about 2.00 Vanadium About 0.05 to about 5.00 Chromium; About 0.05 to about 15.00

the remainder being substantially all iron, the amount of tungsten present being'from about 5% to about 40% of the amount of molybdenum about 10.00

the remainder being substantially all iron, the amount of tungsten present being from about 5% to about 40% of the amount of molybdenum present.

3. A ferrous alloy composition comprising:

- Per cent Carbon About 0.30 to about 1.60 Molybdenum About 0.60 to about 15.00 Tungsten About 0.20 to about 4.50 Cobalt About 1.00 toabout 16.00 Silicon' About 0.05 to about 3.00 Manganese About 0.05 to about 2.00 Vanadium About 0.05 to about 5.00 Chromium About 0.05 to about 15.00

the remainder being substantially all iron, the amount of tungsten present being from about 10% to about 30% of the amount of molybdenum present.

4. A ferrous alloy composition comprising:

the remainder being substantially all iron, the amount of tungsten present being from about 5% to about 16% of the amount of molybdenum present.

5. A ferrous alloy composition comprising:

, Per cent Carbon About 0.30 to about 1.60 Molybdenum About 0.60 to about 15.00 Tungsten About 0.20 to about 3.75 Cobalt Q. About 1.00 to about 16.00 Silicon--..... About 0.05 to about 3.00 Manganese About 0.05 to about 2.00 Vanadium About 0.05 to about 5.00 Chromium About 0.05 to about 15.00

the remainder being substantially all iron, the

Per cent Carbon About 0.30 to about 1.60 Molybdenum About 0.60 to about 15.00 Tungsten About 0.20 to about 2.40 Cobalt About 1.00 to about 16.00 Silicon About 0.05 to about 3.00 Manganese About 0.05'to about 2.00 Vanadium About 0.05 to about 5.00 Chromium About 0.05 to about 15.00

amount of tungsten present being from about 16% to about 25% of the amount of molybdenum present.

6. A ferrous alloy composition comprising:

Per cent Carbon About 0.30 to about 1.60 Molybdenum About 0.60 to about 15.00 Tungsten About 0.20 to about 6.00 Cobalt About 1.00 to about 16.00 Silicon About 0.05 to about 3.00 Manganese About 0.05 to about 2.00 Vanadium About 0.05 to about 5.00 Chromium About 0.05 to about 15.00

the remainder being substantially all iron, the amount of tungsten present being from about 25 -to about 40% of the amount of molybdenum and the remainder being substantially all iron.

8. A ferrous alloy composition consisting of:

Per cent Carbon About .78 Manganese About .08 Silicon About .37 Chromium About 3.58 Tungsten 1 About 2.12 Vanadium About 2.10 Molybdenum About 6.29 Cobalt About 3.98

and the remainder being substantially all iron. 9. A ferrous alloy composition consisting of and the remainder being substantially all iron.

JOSEPH V. EMMONS. 

